Transmission



May 1, 1945.4 V P. @RRV 2,375,031

TRANSMI S S ION Filed June 22,l 1942 pezn er Orr' #EJK/MM one ratio to another, the `nition circuit being effected simultaneouslyr with of the drive control elements.

Patented May l, 1945 Y Palmer Orr, Muncie,

Warner Corporation,

tion of Illinois Ind., assigner `to `lgorg# Chicago, Ill., a corpora- Application June 22, 1942, serial No. 447,902

` Claims.

y This invention relates to motor vehicle transmissions of the type in which the ignition of the vehicle engine is interrupted in order to `relieve the torque load on interengaging drive control elements which` are adapted when engaged to establish a drive `of `one ratio, and, when disengaged, to permit a drive of a diiierent ratio to be established through the transmission. In

transmissions of this type, it is customary to e ploy a manual switch, preferably operated bythe engine throttle, for forcing down the drive from interruption of the igthe energization of an electromagnetic device for controlling the engagement and disengagement Such electromagnetc device is customarily in the for-m `of a solenoid incorporating an ignition restoring switch made operative by the disengagement of vthe drive control elements.` .It is customary to employ relays in the ignition circuit and in the solenoid energizing circuit. In the present-l practice, interruption of the ignitionis effected by short circuiting the. same. This may be designated a closed circuit system. f

One of the characteristics of` such a" closed circuit System is that there is a drain on the battery during each ignition interruption, which is heavier than the normal load imposed by the ignition mechanism. This .not only creates a burden upon thebattery but also deteriorates the circuit breakers of the ignition system.

The primary object of the present invention is to provide an open circuit system in which the ignition circuit is interrupted by opening the same instead of by shorting the same, andto provide such a circuit with a, minimum -of change in the control system now in use in overdrive transmissions. Particularly it is aimed to employ the same solenoid construction including the ignition restoring switch. l

In general, this is accomplished by providing an arrangement in which there is provided an ignition restoring circuit, controlled by-a solenoid operated switch and parallel with an ignition destroying circuit of the open circuit type. -A particular object of the invention is to provide an arrangement of this kind whereinthe solenoid controlledswitch is located directly in the ignition restoring circuit, eliminating relays in this immediate circuit.

lA further object of the invention is to provide a circuit of the type indicated, wherein provision is made for a sucient interval of delay between the operation of the manual switchl which con- Aof the ignition.

trols the `forcingldown of the drive, and the opening of the `ignition circuit, to permit the removal of any coast load that may be imposed upon the vdrive .control elements, prior to the interruption A more specic object of the invention is to provide a transmissioncontrol circuit in which automatic Vmeans is provided for establishing a drive 1of one ratio and in which there is provided manual means for shifting the drive from that ratio back to another ratio, in the form of a delayed opening relay having one set `of contacts adapted, when separated, .to deenergize the solenoid and having, another set of `contactsadapted,

when separated, to open one of two parallel ignitionA circuits, the other of :which at the time is `standing open at a switch that is adapted to be Yclosed by the disengagement of the drive control element, whereby to restore the ignition.

`-Other objects, the advantages and uses of the invention will become more apparent after read- :ing the following specication and claims, and `after consideration of the drawings forming a partof `the specification wherein: f

Fig. 1 isa schematic view ofthe control mechanismof an overdrive transmission embodying` the invention, the position;

Fi'g.f2 is a similar view in directposition.` y r r As an example of one ,form in which the invention may be embodied, I have shown in the drawing the control mechanism ofan overdrive transmission in which the mechanical parts, i. e., fthe planetary gearing, clutches, sun gear rbraking mechanism, and governor are constructed and arranged as shown in `Fig..1 of the pending `application of Harold E.` Carnagua, Serial No. 309;'718,'fi1ed December 18, 1939.

Such an overdrive transmission, which is Well known and extensively used, includes planetary gearing which is adapted, when the sun gear parts `being shown in overdrive with the parts shown thereof is braked, `to transmit an overdrive from the input to the output shaft. and an overrunning clutch which is adapted to pick up the drive in direct ratio when the drive through the planetary gearing is released by freeing the sun rgear for rotation;

The sun` gear braking mechanism includes a slotted locking ring "which is attached to the sun gear. `This slotted ring is shown in the drawing at l2` and cooperates with a] pawl 41 which is adapted to engage in` one of anumber of slots 43 in theperiphery thereof so as-.to` lock the sun lgear against rotation. A solenoid, indicated generally at 6|, is adapted, when energized, to urge the pawl 41 toward engagement with the annular member 42. Such engagement is prevented, as long as the sun gear is rotating, by a. balk ring 50 which has a slipping clutch connection with the sun gear and thus tends to rotate with the locking ring 42 When the pawl 41 is thus biased the engagement may be completed by throttling down the engine, thus placing a coast load on the planetary gearing and causing the sun gear, which has previously been rotating, along with the rest of the planetary gearing, in unison with the driven shaft, to slow down and nally to commence rotating in reverse. This reversal of rotation will carry the balk ring 50 to a position wherein the pawl 41 may pass through an opening 53 in the balk ring, into one of the slots 43 of the locking ring.

` The pawl 41 is connected to the armature 1| of the solenoid 6| by means of a rod 65 which is slidably received in a longitudinal bore in the armature and receives pawl projecting thrust from the armature through the medium of a coil spring `83 engaged between a flange 10 on the rod I65 and a cap 15 on the end of the armature. When the solenoid is energized, the armature 1| is drawn toward the pawl 41, compressing the spring 83, which, when the balk ring 50 permits the pawl 41 to advance, pushes the pawl 41 into one of the slots 43.

The solenoid 6| includes a moving coil 80 and a holding coil 8| both of which are energized for biasing the pawl toward braking position, the coil 80 being deenergized when the pawl 41 goes into the slot 43 and the coil 8| remaining energized for holding the pawl in the slot. The deenergization of the coil 80 is accomplished by a selfclosing switch including contacts 85 and 86, the latter being carried by an arm 81 which is disposed so as to be engaged by a flange 16 on the cap 15 as the armature advances.

' When the circuit through the holding coil 8| is broken, the armature is retracted by a spring 11 engaged between the iiange 16 and an abutment-18 in the solenoid casing.

VThe foregoing structure all forms part of the conventional overdrive transmission disclosed in the pending application Serial No. 309,718 referred to above. Such a conventional overdrive transmission also includes the motor ignition |42, the conventional battery 9| which energizes the solenoid 6| as well as the ignition |42, the ignition switch |43, and a rail switch |01 which functions to open the solenoid circuit when the conventional manually shifted transmission of a motor vehicle is shifted to reverse drive. In the conventional arrangement there is provided a shunt circuit by means of which the ignition is shunted out.

The conventional control arrangement also includes a governor 98 for speed responsive energization of the solenoid, and a manual control device for opening the solenoid circuit when v"the governor 98 is in circuit-closing position, thereby to permit the transmission to be forced b'ack into direct drive when operating in the overdrive range of speed. This manual control customarily includes, in series with the governor 98, a manual switch including contacts |04 bridged by a connector mounted on a push rod |06 which is adapted to be operated by the engine accelerator pedal. It-is also customary to employ a relay having contacts forming part of the solenoid energizing circuit and other contacts forming part of an ignition control circuit, and in addition a delayed action relay for restoring the ignition in the event the normal restoring means fails to function.

The present invention, in addition to securing the desired advantage of interrupting the ignition by opening the circuit thereof instead of shorting it, utilizes a simpler relay mechanism than the conventional relay mechanism referred to above, and at the same time yguards against the failure of ignition restoration. To this end, I provide an ignition restoring circuit which is open when the sun gear locking pawl is engaged and an ignition interrupting circuit, in parallel with the restoring circuit, adapted to be opened by a delayed action relay which also serves to open the solenoid circuit, thus temporarily leavinghboth circuits open. The delayed opening of the relay permits the engine to speed up when the accelerator controlled kick-down switch is actuated for deenergizing the relay, thereby removing, prior to ignition interruption, any coast load that may be imposed on the drive control elements.

The ignition interrupting circuit includes, in series in the order named, the battery 9|, a conductor 200, the ignition switch |43, a conductor 2000i, an ignition interrupting switch 20|, a conductor 202, and the ignition |42.

The switch 20| constitutes one pair of contacts of a delayed action relay 203 including an energizing coil 204 and a second pairof contacts 205, the latter 'being disposed in the solenoid energizing circuit. One of each pair of contacts 20| and 205 is mounted on an arm 206 spring biased as at 201 toward open position. Energization of the coil 204 causes the contacts 20| and 205 to close. Opening of the circuit by which the coil 204 is energized causes the latter to become slowly deenergized, resulting in the delayed opening of the contacts 20| and 205.

The ignition restoring circuit includes, in the order named, the battery 9|, the conductor 200, the ignition switch |43, a conductor 208, an ignition restoring switch including contacts |35 and |36, a conductor 209, and the ignition |42.

The ignition restoring switch is of a self-opening type, the contact |36 being carried by an arm |31 which is biased toward switch opening position as indicated by the schematic representation of a. spring |38. Ignition is restored as a result of the engagement of the arm |31 by an extension of the rod 6-5, when the pawl 41 is retracted.

The primary control circuit for energizing the relay coil 204, includes, in the order named, the current source 9|, a conductor 2|0, the coil 204, a conductor 2| the manual switch |04, |05 and the governor 98.

The solenoid energizing circuit includes, in the order named, the current source 9|, a conductor ||1, the contacts 205, a conductor 2|2, the rail switch |01, a conductor 2|3, and the parallel solenoid coil circuits 8| and 80, 85, 86.

In overdrive operation, the parts are in the position shown in Fig. 1. With the transmission set for forward drive the rail switch |01 will be closed. Upon operation above the overdrive cut-in speed, the governor 98 will close the primaryy control circuit, energizing the coil 204 and causing the contacts 20| and 205 to close. The closing of the contacts 205 establishes the solenoid energizing circuit, causing the pawl 41 to be projected into engagement with the balk Aring 50.' Simultaneously with the closing of the solenoid energizing switch 205, the ignition interrupting switch memos! i 'tion means for energizing the lsame,

201|-willyclose to establish the ign-itionintermpting circuit through whichthe ignition is-energ-ized aslong as the transmission `operates in overdrive. A reversal of torque on the sun gear, eiected by `relaxing the `accelerator pedal, will result; inthe balk ring moving` to a non-blocking position,

permitting the pawlll` to enter the notch 43m the `sun gear flocking ring 42.` The-advancing movement'of the pawl rod 65, which has`previously held the switchi |.35,|3E in closed positiompermits the latter to open under `the. pullfof the spring |38, thus opening the ignitionv restoring circuit. The ignition now will "be `maintained i through the ignition interrupting circuit as previously describedw `With the parts `in the overdrive position,1 and `without -a reduction in speed such as toA open the governor 98, the transmission may be restored to direct drive by opening the manual switchflM, |05. This is accomplished by depressing the accelerator pedal. Opening the lswitch IM, |05lcauses the gradual deenergization of :the coil 2040and, after a short interval .of-v delaytheopening of the switches 205 `and During this interval of delay the vengine may :accelerate `under the increased depression of the acceleratorpedal, so as to remove anycoast load` that `maybe imposed upon the sun gear; Should `the switch20| be opened while' a, coastloadwas imposedion the sun gear there would be no reversallof torque on the sun gear such a's tofree the p`awlf41-from the notch43; i i "The interruption oftheignition while thelsun gear is under normal forward drive load-causes Ya momentary reversal of torque 'which Areleasesthe ,1

pawl yHand permits the spring l1 to retract lthe armature 'll relative to the nowdeenergizedcoils 80 and 8|. The retrograde movement of the pawl rod 65 closes the switch |35, |36 and reestablishes the ignition through the `ignition restoring circuit.

The invention provides a simplified `control circuit of a' type in which the ignition is interrupted by open `circl-iitirn; the same. storing switch |35, |36 is directly included in one of the parallel ignition circuits, without' a relay.

The ignition reparallel circuits 'including :a `switch icontrolled `li-n accordance with the position of said drive control `elements andadapted to Ybe opened when said elements are engaged, and theother of said parallelcircuits including a pair of contacts forming parts: of said relay and adapted to openiin unison with said electromagneticmeans.energizing contacts whilesaid first; mentioned parallel circuit .stands open, and to thereby openacircuit the ignition upon deenergization of the electromagnetic meenam` i w 2; Control 4mechanism as` `defined .in Aclaim` `1, wherein said switch `is adapted to be closed upon disengagement of said drive control elements, :so fas to restore the ignition. ,i l ,i i 3. Control mechanism as `dened in claimwl, lwherein said "relay has `a, delayed opening action, whereby to permit theienginewto accelerate to remove coast .loads from said Linterengaging ,elements prior to interruptionof the ignition.

`4. `Control mechanismfor .a multiple'idrive ratio transmission of a `motor vehicle includingianengine having ignitionlmeans; said control `mechanism comprising positively interengageable drive `control elements `adapted whendisengaged to permit the transmission to operate in' one driveratio `and when engagedto establish another 'drive ratio,

`said `elements beingtsubject to torquekloads when engaged and being freelydis'engageable only when said loads are relieved?, electromagnetic `means adapted when energized tourge one of said ele- `ments in onedirectionof its movement, yielding means to urge said `onefelement in the 'opposite direction, means forestablishing ant energizing circuit through said `electromagnetic `means,` :a relay includinga pairof contacts adapted'to form apart of said energizing circuit, means for'establishing twocircuits `in parallel `through said `igni- -60 'tion'means for energizing the same,.on'e of said i parallelcircuits includinga switch controlledin `accordance with the: position of saiddrive control The other ignition circuit is controlled by a switch which opens and closes simultaneously with the solenoid energizing switch, and may therefore be mounted on a common armature therewith.

While I have described my invention in con- 4 nection with one speciiic embodiment thereof, it

is to be understood that this is by Way of illustration and not by way of limitation and the scope of my invention is deiined solely by the appended claims which should be construed as broadly as the prior art will permit.

I claim: i

1. Control mechanism for a multiple drive ratio transmission `of a motor vehicle including an engine having ignition means; said control mechanism comprising positively interengageable drive control elements adapted when disengaged to permit the transmission to operate in one drive ratio and when engaged to establish another drive ratio, said elements being subject to torque loads when engaged and being freely disengageable only when said loads are relieved, electromagnetic means adapted when energized to urge one of said elements in one direction of its movement, yielding relay including 'a pair of contacts adapted to form4 a part of said energizing circuit, means for establishing two circuits in parallel through said ignielements andfadapted` toy 4openwhen saidiele'- mentsl become engaged and the other of said parallel circuits including a pair of contacts forming part of said relay and adapted to open in unison with said electromagnetic means energizing coni tacts while said iirst mentioned parallel circuits stands open, and to thereby open circuit the ignition upon deenergization of the electromagnetic means, said switch bei-ng adapted to be closed upon disengagement of said drive control elements, so as to restore the ignition, and primary control means for controlling the operation of said relay.

5. Control mechanism as defined in claim 4, wherein said primary control means include an accelerator controlled switch 4adapted to effect deenergization of the electromagnetic means inunison with engine acceleration, and wherein said relay has a delayed opening action to permit said engine acceleration to` remove coast ldads from said drive control elements prior to interruption of the ignition.

6. Transmission control mechanism `for a motor vehicle having an engine including ignition means,

' and having a transmission of a type comprising relatively fast speed driving means including positively interengageable drive control elements i adapted to establish a drive therethrough when oneof "said driving means; said control mechanism comprising electromagnetic means adapted when energized to urge one of said elements in one direction of its movement,.yielding means urging said one elementl in the other direction of its movement, means for establishing an energizing circuit through said electromagnetic means, and means for establishing two circuits in parallel through said ignition means for energizing the same, one of said circuits including a switch adapted to be opened when the drive control elements are engaged and to be closed by disengagement ofsaid elements, and a relay including a rst set of contacts forming a portion of said energizing circuit for the electromagnetic means and a second pair of contacts forming part of the other of said parallel ignition circuits, the last mentioned contacts being adapted to be opened in unison with the deenergization of the electromagnetic means, whereby to open the second of said parallel circuits and interrupt the ignition.

7. Control mechanism for an overdrive transmission of a motor vehicle having an ignition system, planetary gearing including a sun gear adapted to be braked to establish an overdrive through said planetary gearing, direct drive means adapted to automatically establish a direct drive when said sun gear is released for rotation, and positively interengageable elements adapted when engaged to brake said sun gear, said control mechanism comprising electromagnetic means for biasing one of said elements in one direction of its movement, yielding means for biasing said one element in the other direction of its movement, means -for establishing an energizing circuit through said electromagnetic means, a relay including a rst set of contacts forming part of said energizing circuit, and means for establishing two parallel circuits through said ignition means, including a self-opening switch forming part of one of said circuits and adapted to be yclosed by disengagement of said elements and including a second pair of contacts in said relay forming part of the other of said parallel circuits and adapted to be opened upon deenergization of the relay, whereby to interrupt the ignition and relieve the torque load on said drive control element.

8. In a control mechanism as dened in claim 1, primary control means for controlling the operation of said relay, including a governor and a manually operated switch in series therewith.

9. In a control mechanism as deiined in claim 1, primary control means for controlling the operation of said relay, including speed responsive and accelerator operated switches in series therewith, said relay having a delayed opening action permitting the engine to accelerate in unison with the actuation of said accelerator operated switch, suiciently to remove coast loads on said drive control elements prior to the interruption of the ignition. l

10. Control mechanism for an overdrive transmission of a motor vehicle having an ignition system, and having planetary gearing of a type including a sun gear adapted to be braked to establish an overdrive through said planetary gearing, direct drive means adapted to automatically establish a direct drive when said sun gear is released for rotation, and a pawl for braking said sun gear; said control mechanism comprising a solenoid adapted when energized to urge said pawl toward braking position, resilient means for retracting said pawl when the solenoid is deenergized, means for establishing an energizing circuit through said solenoid, a relay including a pair of contacts forming part of said energizing circuit, and means establishing two circuits to said ignition means, one of said circuits including a self-closing switch adapted to be closed by retraction of said pawl and the other of said two circuits including a' second pair of contacts in said relay which are adapted to be opened upon deenergization of the solenoid, thereby to interrupt the ignition and relieve the torque on the sun gear. 1

PALMER ORR. 

